1. Field of the Invention
The present invention relates to an integrated circuit bonding device and a manufacturing method thereof, particularly to an integrated circuit bonding device with highly integrated signal trace lines immune from noise and a manufacturing method thereof.
2. Description of the Related Art
In an integrated circuit manufacturing process, gold lines are bonded between pads on a chip and fingers on a substrate before molding. Thus, the solder balls or pins, connection points hereinafter, of the substrate for connection and signal transmission with external circuits are electrically connected to the pads of the chip.
FIG. 1 is a diagram showing a conventional integrated circuit with bonded gold lines arranged. The integrated circuit comprises a substrate 10, a chip 12 and gold lines 14A, 14B, and 14C. The chip 12 has pads 16A, 16B, and 16C to output signals comprising strobe signals, clock signals, power signals, and ground. The signals are connected to the connecting points 17A, 17B, and 17C of the substrate 10 through gold lines 14A, 14B, and 14C, then connected to other circuits by lines 18A and 18B through via 19A, and 19B or only by line 18C.
The ground ring 15A and power ring 15B surround the chip 12. The power circuit composed by the ground ring 15A and power ring 15B provides the necessary power for chip 12 to operate.
However, noise is easily generated in each signal trace line carrying high frequency signals such as the clock, strobe, and data signals since they interfere with each other. Interfered signals cause failure in chip 12. Therefore, the bonding and layout of the circuit have to be modified to decrease the interference between the signals to improve the reliability of the circuit.
The object of the present invention is to provide an integrated circuit bonding device and a manufacturing method thereof. The signal trace lines transmitting important signals are shielded by the metal lines transmitting the power or ground signals from the pad of the chip to the substrate and follow-up circuits. Because the signal in the power line or ground line is stable and has a stronger electric current, the electromagnetic waves generated from the adjacent signal trace lines are attracted to the power line or ground line. Therefore, the important signals are not interfered with by the adjacent signal trace lines. Using the power line or ground line to shielding metal lines with important signals to solve the interference between the signals and combining the design of the position of pads, the quality of signals is improved.
To achieve the above-mentioned object, the present invention provides an integrated circuit bonding device. The substrate includes a signal connection point and two shielding connection points set at the two sides of the signal connection point. The chip is set on the substrate. There are a signal pad and two shielding pads set at the two sides of the signal pad on the edge of the chip. The signal gold line is coupled to the signal connection point and the signal pad. Two shielding gold lines are coupled to the shielding connection points and the shielding pads and extend along both sides of the signal gold line. The signal trace line is set on the substrate and coupled to the signal connection point. The power circuit is set on the substrate and coupled to the shielding connection points. The power circuit includes two shielding lines extending along both sides of the signal trace line.
In addition, the present invention provides a method to manufacture an integrated circuit device. First, a substrate and a chip are provided. Next, a signal pad is formed on the chip. Two shielding pads are formed at both sides of the signal pad on the edge of the chip. Two shielding connection points are formed on the substrate responding to the shielding pads. Then, a signal connection point is formed between the shielding connection points. Next, a signal trace line is formed for coupled to the signal connection point. A signal gold line is formed for coupled to the signal pad and the signal connection point. Next, two shielding gold lines are formed for coupled to the shielding pads and the shielding connection point and extending along both sides of the signal gold line. Finally, a power circuit comprising two shielding lines extending along both sides of the signal trace line is formed on the substrate.